Development of 2-dimensional Profile Automatic Measuring Machine Using Pinhole Image Projection Method

Abstract

In this research, a machine for measuring a 2-dimensional profile of the inner wall (not an “edge portion”) at any height from the bottom of a small hole in machine parts such as a die, a nozzle and a gauge, is developed. An automatic measurement is realized by installing a preceding instrument that detects the whole profile of the parts. The 2-dimensional profile is measured using the parts that have a plane surface, a concave and a convex surface with the curvature radius of 0.5mm, a right-angled edge and corner. The experimental result shows that the 2-dimensional profile except for the right-angled corner can be measured with an error smaller than ±0.2μm at the middle height of the specimen. It is difficult to measure the profile within the region of 0.15mm along both sides from the corner point.